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During X-ray scanning imaging, the X-ray dose received by CdZnTe photon counting detectors varies dynamically because of the different absorption coefficients that occur at different locations in the object being imaged. This paper explores the phenomenon of count rate relaxation in CdZnTe detectors during X-ray dose mutations and studies the intrinsic relationship of this phenomenon with the polarization effect. The characterization of the count rate relaxation processes of CdZnTe detectors at three typical X-ray doses are studied in detail. It is concluded that the count rate relaxation process of the CdZnTe detectors correspond to the polarization process, which can be divided into three stages according to the accumulation rate of space charges, and the relaxation time depends on the settling time of the polarizing electric field. In addition, the effects of temperature and bias voltage on the relaxation phenomenon of CdZnTe detectors are studied. The results show the relaxation process of the count rate can be regulated by adjusting the temperature and bias voltage of the CdZnTe detectors. Changes in temperature and bias mainly act on the trapping and de-trapping processes of deep-level traps, thereby affecting the establishment of the polarization electric field, which further proves the close relationship between the count rate relaxation phenomenon and the polarization effect. Finally, the effects of count rate relaxation on DR image quality are discussed based on self-built DR imaging system. • The relaxation phenomenon of the CdZnTe X-ray photon counting detector was proposed. • The dominant factors affecting the relaxation process at different X-ray doses was determined. • The relationship between polarization and relaxation of high-flux X-ray CdZnTe detectors was examined. • The effects of bias and temperature on the relaxation phenomenon were characterized. • The deterioration of the relaxation phenomenon on the quality of the image was shown. [ABSTRACT FROM AUTHOR]

Due to the development of sequence technology and decreased cost, many whole genome sequences have been obtained. As a result, extensive genetic variations have been discovered from many populations and germplasms to understand the genetic diversity of soybean (Glycine max [L.] Merr.). However, assessing the quality of variation is essential because the published variants were collected using different bioinformatic methods and parameters. Furthermore, despite the enhanced genome contiguity and more efficient filling of "N" stretches in the new reference genome, there remains a dearth of endeavors to verify the caliber of variations present in it. The primary goal of this research was to discern a dependable set of SNPs that can withstand reconciliation across multiple reference genomes. Additionally, the investigation aimed to reconfirm the variations through the utilization of numerous whole genome sequencing data obtained from publicly available databases. Based on the result, we created datasets that comprised the thoroughly verified SNP coordinates between the reference assemblies. The resulting "SoyDBean" database is now publicly accessible through the following URL: http://soydbean.plantprofile.net/. [ABSTRACT FROM AUTHOR]

Electronic screens have become an integral part of modern life, accompanied with growing concerns for children's neuropsychological development. This study aimed to evaluate the associations between measures of early life screen exposure and hyperactive behaviors among preschool children. The study also aimed to investigate their cumulative effects and the critical window for these associations. A cross-sectional survey was conducted among 52 625 mother-child dyads at preschools in LongHua District of Shenzhen, China. A self-administered structured questionnaire was used to assess socio-demographic characteristics, duration of children's electronic screen exposure in each of the first 3 years following birth and the presence of current hyperactive behaviors. A series of logistic regression models were used to examine the relationship between previous screen time and current hyperactive behaviors. A crossover analysis was used to explore the critical window for a significant relationship between screen time and hyperactive behaviors. We found that exposure to electronic screens in the first 3 years of life was associated with hyperactive behaviors in preschool children. A cumulative effect was shown in children with an average daily screen time less than 60 min, with adjusted ORs increasing from 1.262 to 1.989 as screen exposure years increased from 1 to 3 years. A critical window was identified in that children in the first 2 years after birth were vulnerable to electronic screen exposure. Exposure to televisions, mobile phones, and computers were all related to elevated risks for hyperactive behaviors. In conclusion, early screen exposure appears to increase the risk for hyperactive behaviors in preschool children with the presence of a cumulative effect, a critical window and different electronic screens having similar effects. [ABSTRACT FROM AUTHOR]

The elementary electronic‐logic‐gates, performing basic logic functions using electric signals as input, act as a building block of modern digital circuits. Intriguingly, the optoelectronic‐logic‐gates (OLGs), composed of optical devices, are emerging as a new logic platform which enables faster and large‐capacity data transmission and processing by using photons as input. However, the strict operation principle of classic optical devices, for example, the unidirectional photoresponse of the photodetector, restricts the functional enrichment of OLGs. Herein, reprogrammable OLGs in a photoelectrochemical (PEC)‐environment are reported by employing gallium‐nitride semiconductor p–n nanowires as photoelectrodes where bidirectional photocurrent is achieved, leading to the demonstration of various binary OLGs including "NOT", "XOR", and "OR". Strikingly, thanks to the versatile tunability of PEC‐photoelectrodes, the logic function of these OLGs is switchable by simply adjusting programming inputs including light intensity, bias voltage, electrolyte condition, and the physicochemical properties of the nanowire surface. Most importantly, unique ternary OLGs, for example, ternary "OR" gates, can also be realized based on binary ones by just tuning their applied bias for higher logic complexity applications, without changing the device architecture. Such reprogrammable binary and ternary OLGs could provide a new avenue toward next‐generation logic circuits for fast computing and data‐processing in the future. [ABSTRACT FROM AUTHOR]

Key message: PAP-FcK and PSA-FcK prostate cancer antigenic proteins transiently co-expressed in plant induce their specific humoral immune responses in mice. Prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) have been considered as immunotherapeutic antigens for prostate cancer. The use of a single antigenic agent is unlikely to be effective in eliciting immunotherapeutic responses due to the heterogeneous and multifocal nature of prostate cancer. Thus, multiple antigens have been combined to enhance their anti-cancer effects. In the current study, PSA and PAP were fused to the crystallizable region (Fc region) of immunoglobulin G1 and tagged with KDEL, the endoplasmic reticulum (ER) retention signal motif, to generate PSA-FcK and PAP-FcK, respectively, and were transiently co-expressed in Nicotiana benthamiana. Western blot analysis confirmed the co-expression of PSA-FcK and PAP-FcK (PSA-FcK + PAP-FcK) with a 1:3 ratios in the co-infiltrated plants. PSA-FcK, PAP-FcK, and PSA-FcK + PAP-FcK proteins were successfully purified from N. benthamiana by protein A affinity chromatography. ELISA showed that anti-PAP and anti-PSA antibodies successfully detected PAP-FcK and PSA-FcK, respectively, and both detected PSA-FcK + PAP-FcK. Surface plasmon resonance (SPR) analysis confirmed the binding affinity of the plant-derived Fc fusion proteins to FcγRI/CD64. Furthermore, we also confirmed that mice injected with PSA-FcK + PAP-FcK produced both PSA- and PAP-specific IgGs, demonstrating their immunogenicity. This study suggested that the transient plant expression system can be applied to produce the dual-antigen Fc fusion protein (PSA-FcK + PAP-FcK) for prostate cancer immunotherapy. [ABSTRACT FROM AUTHOR]

This study systematically investigates the optical performance of N-polar deep-ultraviolet light-emitting diodes (DUV LEDs) in consideration of different quantum structures in the active region, with a highlight on various thicknesses of quantum barrier (QB), quantum well (QW), and the electron-blocking layer (EBL). The results show that the internal quantum efficiency (IQE), as well as light output power (LOP) of N-polar DUV LED, is not sensitive to QB thickness. On the contrary, the LOP and IQE performance can be significantly enhanced by increasing the QW thickness from 2 to 4 nm. Moreover, a saturated LOP in the N-polar DUV LEDs can be observed after QW thickness increased to a certain level as there is a trade-off between boosted carrier concentration and decreased wave function overlap in the active region. Lastly, the impact of the EBL on the optical performance of the N-polar DUV LED is also investigated. Specifically, a thicker EBL or a higher Al composition in the EBL leads to an increase in the turn-on voltage and series resistance while the LOP value remains unchanged. These findings lay the foundation for the development of high-performance N-polar DUV LEDs of the future. [ABSTRACT FROM AUTHOR]

We investigated 98 Taiwanese patients with molecularly unassigned hereditary spastic paraplegia (HSP) and found none of them had the NOTCH2NLC GGC repeat expansion, which is the cause of neuronal intranuclear inclusion disease (NIID). Our findings suggest that the NOTCH2NLC GGC repeat expansion may not contribute to HSP. [ABSTRACT FROM AUTHOR]

One major breakthrough in cystic fibrosis research in the past decade is the development of drugs that target the root cause of the disease — dysfunctional CFTR protein. One of the compounds, Ivacaftor or Kalydeco, which has been approved for clinical use since 2012, acts by promoting the gating function of CFTR. Our recent studies have led to a gating model that features energetic coupling between nucleotide-binding domain (NBD) dimerization and gate opening/closing in CFTR's transmembrane domains (TMDs). Based on this model, we showed that ATP analogs can enhance CFTR gating by facilitating NBD dimerization, whereas Ivacaftor works by stabilizing the open channel conformation of the TMDs. This latter idea also explains the near omnipotence of Ivacaftor. Furthermore, this model identifies multiple approaches to synergistically boost the open probability of CFTR by influencing distinct molecular events that control gating conformational changes. [ABSTRACT FROM AUTHOR]

The biophysical properties of blood have been considered as promising indices for effectively screening the cardiovascular diseases. In this study, a method for the continuous and simultaneous measurement of the biophysical properties of blood, including viscosity, viscoelasticity, and RBC (red blood cell) aggregation is suggested, using a microfluidic device. The microfluidic device has two inlets (A, B), two outlets (A, B), two identical side channels, and one bridge channel. To sequentially induce steady and transient flows of blood samples, a blood sample is carefully delivered into the inlet (A) at a pulsatile flow rate (Q) (Qmax = 1 mL h−1, Qmin = 0 mL h−1, T = 240 s). By operating a pinch valve connected to the outlet (A), the blood flow is stopped or passed in the left-lower side channel. Three biophysical properties of the blood sample are quantified by analyzing the flow rate in the left-upper side channel (QμPIV), the image intensity in the left-lower side channel (〈I〉Blood), and the blood-filled width in the right-lower side channel (αBlood). First, based on the modified parallel flow method, the blood viscosity (μBlood) is measured by analyzing the variation in αBlood. Second, using a discrete fluidic circuit model, the time constant (λ) is evaluated by analyzing temporal variations in QμPIV and 1/(1 −αBlood). Then, the blood elasticity (GBlood) is calculated by assuming the linear Maxwell model (i.e., λ = μBlood/GBlood). Third, the RBC aggregation is quantified in terms of three parameters (〈I〉Slope, ARatio, and AUpp) obtained by analyzing temporal variations in the image intensity. From the experimental demonstrations using various blood samples, it is concluded that the proposed method has the ability to measure the biophysical properties of blood with consistency, as compared with the previous methods. In the near future, the proposed method will be employed for evaluating variations in the biophysical properties of blood, circulating in the extracorporeal rat bypass loop. [ABSTRACT FROM AUTHOR]

The activation of NF-κB downstream of T cell receptor (TCR) engagement is a key signaling step required for normal lymphocyte function during the adaptive immune response. During TCR signaling, the adaptor protein Bcl10 is inducibly recruited to the CARD11 scaffold protein as part of a multicomponent complex that induces IκB kinase (IKK) activity and NF-κB activation. Here, we show that a consequence of this recruitment is the TCR-induced conjugation of Bcl10 with linear-linked polyubiquitin chains to generate the signaling intermediate Lin(Ub)n- Bcl10, which is required for the association of Bcl10 with the NEMO subunit of the IKK complex. The TCR-induced generation of Lin(Ub)n-Bcl10 requires Bcl10 lysines 17, 31, and 63, CARD11, MALT1, and the HOIP subunit of the linear ubiquitin chain assembly complex (LUBAC) but not the HOIP accessory protein SHARPIN. CARD11 promotes signal-induced Lin(Ub)n-Bcl10 generation by co-recruiting Bcl10 with HOIP, thereby bringing substrate to enzyme. The CARD11-HOIP interaction is rendered TCR-inducible by the four autoinhibitory repressive elements in the CARD11 inhibitory domain and involves the CARD11 coiled-coil domain and two independent regions of HOIP. Interestingly, oncogenic CARD11 variants associated with diffuse large B cell lymphoma spontaneously induce Lin(Ub)n-Bcl10 production to extents that correlate with their abilities to activate NF-κB and with their enhanced abilities to bind HOIP and Bcl10. Our results define molecular determinants that control the production of Lin(Ub)n-Bcl10, an important signaling intermediate in TCR and oncogenic CARD11 signaling. [ABSTRACT FROM AUTHOR]

• Time-varying dynamic coefficients of journal bearing are estimated without the tachometers. • Instantaneous angular speed of the journal bearing-rotor system is extracted. • An iteration strategy based on the square-root cubature Kalman filter is formulated. Accurate estimation of time-varying dynamic coefficients (TVDCs) of the journal bearing is important for the dynamic characteristic analysis of rotating machinery. This paper proposes a novel estimation method to identify TVDCs of journal bearings without the tachometers. Firstly, a phase-based method is introduced to extract the instantaneous angular speed (IAS) from the shaft displacement. Secondly, an iteration strategy based on the square-root cubature Kalman filter (SRCKF) is developed to estimate the TVDCs in the time domain. The state-space model and the measured shaft displacements of the journal bearing-rotor system have been applied in the estimation process. The proposed method can estimate TVDCs of journal bearing under speed-variable conditions without a tachometer by combining the phase-based and SRCKF methods. Finally, the simulation and experiments studies are conducted to demonstrate the effectiveness of the proposed methods. The results show that the proposed method can efficiently estimate TVDCs of the journal bearing under speed-variable conditions and at varied measurement noise levels. [ABSTRACT FROM AUTHOR]

In recent years, using Siamese network (SiamN) for visual tracking has witnessed a great success in terms of accuracy and efficiency. Nevertheless, most SiamN-based trackers employ shallow network such as AlexNet to extract the top-layer features as target representation that are less discriminative, usually leading to tracking performance degeneration when suffering from large deformation and similar distractors. A straightforward idea to address this issue is to replace the backbone network of SiamN with deeper ResNet. However, this cannot boost performance much due to the low resolution of highlevel feature maps with useful spatial details losing. To address this issue, the authors propose a lightweight yet effective feature agglomeration module (FAM) to adaptively fuse low-level and high-level features for robust tracking. Specifically, they first develop a generalised non-local attention module to enhance the discriminative capability of high-level semantic features. Then, they design an inception-like module to enhance the representative power of low-level features with more spatial details. Both types of features are then adaptively fused in the FAM to complement their characteristics. Extensive evaluations on OTB-2015 and VOT2017 challenge demonstrate that the proposed tracker consistently achieves favourable performance against several state-of-the-art trackers and runs at 50 fps. [ABSTRACT FROM AUTHOR]

Recommending personalized content from massive data for users is the key function of the recommendation system. The recommendation process of the traditional recommendation systems is often regarded as static, which cannot reflect the changes of user's real-time interest. This paper addressed this problem and presented a recommendation model that leverages the ability of deep learning methods to effectively deal with decision-making problems. In this model, a state generation module containing gate recurrent unit (GRU) and attention network was designed to obtain user's long and short-term preferences as well as history scores. Then, an actor-critic algorithm was employed to imitate the real-time recommendations. We trained the proposed model and evaluated it on four wellknown public datasets. It is proved that the proposed model is superior to existing recommendation models. [ABSTRACT FROM AUTHOR]

A microscale metal-organic framework [Eu(atpt) 1.5 (phen)(H 2 O)] n (H 2 atpt = 2-aminoterephthalic acid, phen = 1,10-phenanthroline) (Eu-MOF) was synthesized and characterized by elemental analysis, luminescence spectrum, powder X-ray diffraction, dynamic light scattering and scanning electron microscope. The fluorescence response of Eu-MOF to metal ions and aldehydes showed that Eu-MOF is highly selective to Fe(III), Al(III) and 2-hydroxy-1-naphthaldehyde (2-OH-NA). Eu-MOF could be utilized as a multi-functional fluorescence chemosensor for Fe(III), Al(III) and 2-hydroxy-1-naphthaldehyde (2-OH-NA). The detection limit of Fe(III), Al(III) and 2-OH-NA was 45, 10 and 36 μM, respectively. The corresponding sensing mechanisms were explored. [ABSTRACT FROM AUTHOR]

The air flow'field of a foreign fiber separator is simulated numerically. Effects of design parameters such as the nozzle diameter and entrance width of the noil box on the air velocity along nozzle axis, turbulence intensity, and jet deflection distance are studied. Larger nozzle diameters and larger entrance widths of the noil box are advantageous to the elimination of foreign fibers. The results provide a theoretical basis for the design of foreign fiber separators. [ABSTRACT FROM AUTHOR]

We demonstrate the light trapping effect in amorphous silicon (a-Si:H) layer by inserting a layer of periodic molybdenum disc array (MDA) between the a-Si:H layer and the quartz substrate, which forms a three-layer structure of Si/MDA/SiO2. The MDA layer was fabricated by a new cost-effective method based on nano-imprint technology. Further light absorption enhancement was realized through altering the topography of MDA by annealing it at 700°C. The mechanism of light absorption enhancement in a-Si:H interfaced with MDA was analyzed, and the electric field distribution and light absorption curve of the different layers in the Si/MDA structure under light illumination of different wavelengths were simulated by employing numerical finite difference time domain (FDTD) solutions. [ABSTRACT FROM AUTHOR]

The use of next-generation sequencers and advanced genotyping technologies has propelled the field of plant genomics in model crops and plants and enhanced the discovery of hidden bridges between genotypes and phenotypes. The newly generated reference sequences of unstudied minor plants can be annotated by the knowledge of model plants via translational genomics approaches. Here, we reviewed the strategies of translational genomics and suggested perspectives on the current databases of genomic resources and the database structures of translated information on the new genome. As a draft picture of phenotypic annotation, translational genomics on newly sequenced plants will provide valuable assistance for breeders and researchers who are interested in genetic studies. [ABSTRACT FROM AUTHOR]

This study investigates newcomer proactive behaviour through the lens of person-environment ( PE) fit theory. Two competing theories of autonomy-based needs-supplies ( NS) fit were hypothesized to impact both newcomer proactive behaviours and socialization outcomes. Results from two waves of data collected from organizational newcomers indicate support for a self-regulatory form of relationship, where individuals engaged in different types of proactive behaviours most often when organizational supplies for autonomy did not match their personal needs. Specific types of proactive behaviours including feedback seeking, positive framing, general socializing, networking, and information seeking also mediated the impact of NS misfit onto certain socialization outcomes. Much can still be learnt about PE fit and proactive behaviours through further integration of ideas from both fields of research. Practitioner points Employers need to understand which types of proactive behaviours to encourage in newcomers in order for them to become active contributors in their new organizational settings., Employers looking to manage newcomer proactive behaviours through autonomy need to carefully manage the amount of autonomy provided relative to individual needs for autonomy. [ABSTRACT FROM AUTHOR]

Red blood cell (RBC) deformability has been considered a potential biomarker for monitoring pathological disorders. High throughput and detection of subpopulations in RBCs are essential in the measurement of RBC deformability. In this paper, we propose a new method to measure RBC deformability by evaluating temporal variations in the average velocity of blood flow and image intensity of successively clogged RBCs in the microfluidic channel array for specific time durations. In addition, to effectively detect differences in subpopulations of RBCs, an air compliance effect is employed by adding an air cavity into a disposable syringe. The syringe was equally filled with a blood sample (Vblood = 0.3 mL, hematocrit = 50%) and air (Vair = 0.3 mL). Owing to the air compliance effect, blood flow in the microfluidic device behaved transiently depending on the fluidic resistance in the microfluidic device. Based on the transient behaviors of blood flows, the deformability of RBCs is quantified by evaluating three representative parameters, namely, minimum value of the average velocity of blood flow, clogging index, and delivered blood volume. The proposed method was applied to measure the deformability of blood samples consisting of homogeneous RBCs fixed with four different concentrations of glutaraldehyde solution (0%–0.23%). The proposed method was also employed to evaluate the deformability of blood samples partially mixed with normal RBCs and hardened RBCs. Thereafter, the deformability of RBCs infected by human malaria parasite Plasmodium falciparum was measured. As a result, the three parameters significantly varied, depending on the degree of deformability. In addition, the deformability measurement of blood samples was successfully completed in a short time (∼10 min). Therefore, the proposed method has significant potential in deformability measurement of blood samples containing hematological diseases with high throughput and precise detection of subpopulations in RBCs. [ABSTRACT FROM AUTHOR]

This paper investigates how different types of person–environment (P–E) fit work together to influence job satisfaction. One field study and a re‐analysis of Cable and DeRue's (2002) data were conducted to investigate the inter‐relationships linking different types of fit perceptions and job satisfaction. An employment relationship model describing how person–organisation values congruence (OVC), demands–abilities (D–A), and needs–supplies (N–S) fit perceptions relate to each other and job satisfaction is proposed and tested. Results support a model where N–S fit mediated the impact of both OVC and D–A fit on job satisfaction. Furthermore, OVC was related also to satisfaction both directly and indirectly, whereas D–A fit was only related to satisfaction via N−S fit. [ABSTRACT FROM AUTHOR]

Spleen plays an important role in removing old and damaged red blood cells and malaria-infected erythrocytes. When malaria parasites invade the spleen and induce splenomegaly, splenic function tends to be impaired. Thus, the inhibition of splenomegaly is strongly required to protect the spleen. In this study, malaria-induced splenomegaly is inhibited by injecting genistein into a Plasmodium berghei -infected ICR mouse. To explain this phenomenon, the effect of genistein in spleen and liver of malaria-infected mice was evaluated by histological examination. Malaria parasites disrupted splenic architecture. After treating genistein, the disrupted architecture in which red and white pulp regions were clearly separated in recovered to uninfected ones. Changes in biophysical properties of blood were studied by measuring the viscosity of blood collected from malaria-infected and uninfected mice using a microfluidic viscometer. Genistein also had a negligible influence on variation in blood viscosity. The enzymatic activity and expression pattern of proteins were then investigated to explain the genistein effect on malaria-induced splenomegaly. Genistein is a potential drug for splenomegaly in P. berghei -infected mouse. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) is the most widely discussed and clinically employed method for the differential diagnosis of oligodendrogliomas; however, MRI occasionally produces unclear results that can hinder a definitive oligodendroglioma diagnosis. The present study describes the case of a 34-year-old man that suffered from headache and right upper-extremity weakness for 2 months. Based on the presurgical evaluation, it was suggested that the patient had a World Health Organization (WHO) grade II-II glioma, meningioma or arteriovenous malformation (AVM), with unclear radiological manifestations. Postsurgical pathological assessment confirmed the tumor to be an anaplastic oligodendroglioma (WHO grade III). This case is notable due to the confusing radiological manifestation of a mushroom-shaped anaplastic oligodendroglioma in the parietal-temporal-occipital region, which provided a potential source of misdiagnosis for meningioma and AVM. [ABSTRACT FROM AUTHOR]

China is home to three subspecies of tiger Panthera tigris but there are no estimates of the size of any of the populations. We detected a population of the Endangered Amur tiger Panthera tigris altaica in Hunchun Nature Reserve in Jilin Province using both mitochondrial DNA and nuclear microsatellite loci. Four male and one female tigers were detected, indicating the potential for a small breeding group. However, genetic diversity was low overall, with six loci showing a heterozygote deficiency and a mean of 2.55 alleles per locus. This study is the first estimate of the wild Amur tiger population in China to use non-invasive techniques, and the presence of a female tiger indicates this is a potentially viable population. We provide baseline genetic diversity estimates to support monitoring of the population. The small number of tiger scats located indicates the importance of continuing the current conservation efforts for this tiger subspecies in Hunchun Nature Reserve. Such efforts include reducing poaching of tigers and their prey, and implementation of management plans to encourage the persistence and recovery of tigers in this area. [ABSTRACT FROM AUTHOR]

Inverter voltage control is an important task in the operation of a DC/AC microgrid system. To improve the inverter voltage control dynamics, traditional approaches attempt to measure and feedforward the load current, which, however, needs remote measurement with communications in a microgrid system with distributed loads. In this paper, a load current observer (LCO) based control strategy, which does not need remote measurement, is proposed for sinusoidal signals tracking control of a three-phase inverter of the microgrid. With LCO, the load current is estimated precisely, acting as the feedforward of the dual-loop control, which can effectively enlarge the stability margin of the control system and improve the dynamic response to load disturbance. Furthermore, multiple PR regulators are applied in this strategy conducted in a stationary αβ frame to suppress the transient fluctuations and the total harmonic distortion (THD) of the output voltage and achieve faster transient performance compared with traditional dual-loop control in a rotating dq0 frame under instantaneous change of various types of load (i.e., balanced load, unbalanced load, and nonlinear load). The parameters of multiple PR regulators are analyzed and selected through the root locus method and the stability of the whole control system is evaluated and analyzed. Finally, the validity of the proposed approach is verified through simulations and a three-phase prototype test system with a TMS320F28335 DSP. [ABSTRACT FROM AUTHOR]

Detecting rivers from remotely sensed imagery is an initial yet important step in space-based river studies. This paper proposes an automatic approach to enhance and detect complete river networks. The main contribution of this work is the characterization of rivers according to their Gaussian-like cross-sections and longitudinal continuity. A Gabor filter was first employed to enhance river cross-sections. Rivers are better discerned from the image background after filtering but they can be easily corrupted owing to significant gray variations along river courses. Path opening, a flexible morphological operator, was then used to lengthen the river channel continuity and suppress noise. Rivers were consistently discerned from the image background after these two-step processes. Finally, a global threshold was automatically determined and applied to create binary river masks. River networks of the Yukon Basin and the Greenland Ice Sheet were successfully detected in two Landsat 8 OLI panchromatic images using the proposed method, yielding a high accuracy (~97.79%), a high true positive rate (~94.33%), and a low false positive rate (~1.76%). Furthermore, experimental tests validated the high capability of the proposed method to preserve river network continuity. [ABSTRACT FROM AUTHOR]

The micralgae-based biofuel obtained from dairy wastewater (DWW) is considered a promising source of energy. However, this process consumes water due to the concentration of wastewater being normally too high for some micoralgae cultivation, and dilution is always needed. In this work, the cultivation of microalgae has been examined in non-recirculated water (NR) and recirculated water systems (R). The growth of Chlorella zofingiensis and the nutrient removal of DWW have been recorded. The comparison indicates the R had a little more advantage in biomass and lipid output (1.55, 0.22 g, respectively) than the NR (1.51, 0.20 g, respectively). However, the total chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), and total phosphorus (TP) removals of the R were lower than those of the NR system during the culture. The highest removal of total COD, TKN, and TP were 85.05%, 93.64%, and 98.45%, respectively. Furthermore, no significant difference has been observed in the higher heating value and lipid content of the biomass of the R and NR. The results show the R can save 30% of the total water input during the culture. All above results indicate the R system has great potential in industry. [ABSTRACT FROM AUTHOR]

Background TNF-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor receptor superfamily and its serum level is known to be closely associated with future cardiovascular events and prognosis of various cardiovascular diseases. We investigated whether serum TRAIL levels are associated with the severity of acute ischemic stroke and specific stroke subtype. Methods We used an enzyme-linked immunosorbent assay to measure the serum TRAIL levels of 293 patients with acute ischemic stroke within 7 days of onset. Stroke subtype was classified as large artery atherosclerosis, cardioembolism, small vessel occlusion and other determined etiology. We used National Institute of Health Stroke Scale (NIHSS) score of first hospital day and stroke volume on diffusion-weighted imaging within 7 days of stroke onset for measuring the severity of acute ischemic stroke. Results The level of serum TRAIL showed significant negative correlations with NIHSS score and stroke volume. Serum TRAIL levels significantly decreased as the tertile of NIHSS score and stroke volume increased. The relative risk of patients with serum TRAIL < 64.0 pg/mL for the presence of highest tertile of NIHSS score was significantly increased (adjusted OR [95%CI]; 7.07 [3.64–13.74]). Regarding stroke volume, the relative risk of patients with serum TRAIL < 71.5 pg/mL for the presence of highest tertile of stroke volume was also significantly increased (adjusted OR [95%CI]; 2.81 [1.61–4.92]). There are no significant differences of serum TRAIL level among stroke subtypes. Conclusions Low serum TRAIL levels were significantly associated with the acute ischemic stroke severity. This finding suggests that serum TRAIL might also have a role in acute ischemic stroke as well as other cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Epoxy asphalt binder is a completely different thermosetting paving material from traditional modified asphalt binders. To character its properties, standard test method of tensile properties for plastics is borrowed. However, the correlations within tensile properties and road-paving properties like i.e. temperature stability and durability are not clear. In this paper, dynamic shear rheometer (DSR) was used to test its rheological performances in comparison of base asphalt binder and SBS modified asphalt binder. Fluorescence microscope was used to trace the microscope structure evolution process, and Scanning Electron Microscope (SEM) to observe the fracture profile of epoxy asphalt at −40 °C. Results indicate that creep strains of epoxy asphalt are 10 −7 to 10 −2 times as much as that of base asphalt, and 10 −6 to 10 −2 times of Styrene–Butadiene–Styrene (SBS) modified asphalt. Creep and recovery experiments find that epoxy asphalt is completely elastic after 100 loading–unloading circles, which implies that epoxy asphalt has a remarkable anti-rutting potential, on the contrary, base asphalt binder and SBS modified asphalt binder are in the state of Newton liquids under the same experimental conditions. Temperature sweep by DSR shows that epoxy asphalt has a superior thermal stability from −30 °C to 120 °C, which is verified by the two transition peaks at −22 °C and 28 °C obtained from dynamic mechanical thermal analyzer (DMTA). High performances of epoxy asphalt binder are attributed to crosslinked bimodal networks during thermal cure which were observed by fluorescence microscope. These experiments qualify the excellent properties of epoxy asphalt binder from the viewpoint of rheology, and the consistency within the rheological tests verify the feasibility of using temperature sweep to character the temperature stability of epoxy asphalt binder. [ABSTRACT FROM AUTHOR]

Cystic fibrosis (CF), one of the most common lethal genetic diseases, is caused by loss-of-function mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which encodes a chloride channel that, when phosphorylated, is gated by ATP. The third most common pathogenic mutation, a glycine-to-aspartate mutation at position 551 or G551D, shows a significantly decreased open probability (P0) caused by failure of the mutant channel to respond to ATP. Recendy, a CFTR-targeted drug, VX-770 (Ivacaftor), which potentiates G551D-CFTR function in vitro by boosting its P0, has been approved by the FDA to treat CF patients carrying this mutation. Here, we show that, in the presence of VX-770, G551D-CFTR becomes responsive to ATP, albeit with an unusual time course. In marked contrast to wild-type channels, which are stimulated by ATP, sudden removal of ATP in excised inside-out patches elicits an initial increase in macroscopic G551D-CFTR current followed by a slow decrease. Furthermore, decreasing [ATP] from 2 mM to 20 µM resulted in a paradoxical increase in G551D-CFTR current. These results suggest that the two ATP-binding sites in the G551D mutant mediate opposite effects on channel gating. We introduced mutations that specifically alter ATP-binding affinity in either nucleotide-binding domain (NBDl or NBD2) into the G551D background and determined that this disease-associated mutation converts site 2, formed by the head subdomain of NBD2 and the tail subdomain of NBDl, into an inhibitory site, whereas site 1 remains stimulatory. G551E, but not G551K or G551S, exhibits a similar phenotype, indicating that electrostatic repulsion between the negatively charged side chain of aspartate and the -ɣ-phosphate of ATP accounts for the observed mutational effects. Understanding the molecular mechanism of this gating defect lays a foundation for rational drug design for the treatment of CF. [ABSTRACT FROM AUTHOR]

Red blood cells (RBCs) are important to dictate hemorheological properties of blood. The shear-thinning effect of blood is mainly attributed to the characteristics of the RBCs. Variations in hemorheological properties alter flow resistance and wall shear stress in blood vessels. Therefore, detailed understanding of the relationship between the hemorheological and hemodynamic properties is of great importance. In this study, blood viscosity and blood flow were simultaneously measured in the same microfluidic device by monitoring the flow-switching phenomenon. To investigate blood flows according to hemorheological variations, the flow rate of blood samples (RBCs suspended in autologous plasma, dextrantreated plasma, and in phosphate buffered saline solution) was precisely controlled with a syringe pump. Velocity profiles of blood flows were measured by using a micro-particle image velocimetry technique. The shape of velocity profiles was quantified by using a curve-fitting equation. It is found that the shape of the velocity profiles is highly correlated with blood viscosity. To demonstrate the relationship under ex vivo conditions, biophysical properties and velocity profiles were measured in an extracorporeal rat bypass loop. Experimental results show that increased blood viscosity seems to induce blunt velocity profile with high velocity component at the wall of the microchannel. Simultaneous measurement of blood viscosity and velocity profile would be useful for understanding the effects of hemorheological features on the hemodynamic characteristics in capillary blood vessels. [ABSTRACT FROM AUTHOR]

The tolerance/resistance of the electronic devices to extremely harsh environments is of supreme interest. Surface effects and chemical corrosion adversely affect stability and operation uniformity of metal oxide resistive memories. To achieve the surrounding-independent behavior, the surface modification is introduced into the ZnO memristors via incorporating fluorine to replace the oxygen sites. F-Zn bonds is formed to prevent oxygen chemisorption and ZnO dissolution upon corrosive atmospheric exposure, which effectively improves switching characteristics against harmful surroundings. In addition, the fluorine doping stabilizes the cycling endurance and narrows the distribution of switching parameters. The outcomes provide valuable insights for future nonvolatile memory developments in harsh electronics. [ABSTRACT FROM AUTHOR]

Adzuki bean, also known as red bean ( Vigna angularis), with 2 n = 22 chromosomes, is an important legume crop in East Asian countries, including China, Japan, and Korea. For single nucleotide polymorphism (SNP) discovery, we used Vigna accessions, V. angularis IT213134 and its wild relative V. nakashimae IT178530, because of the lack of DNA sequence polymorphism in the cultivated species. Short read sequences of IT213134 and IT178530 of approximately 37 billion and 35 billion bp were produced using the Illumina HiSeq 2000 system to a sequencing depth of 61.5× and 57.7×, respectively. After de novo assembly was carried out with trimmed HiSeq reads from IT213134, 98,441 contigs of various sizes were produced with N50 of 13,755 bp. Using Burrows-Wheeler Aligner software, trimmed short reads of V. nakashimae IT178530 were successfully mapped to IT213134 contigs. All sequence variations at the whole-genome level were examined between the two Vigna species. Of the 1,565,699 SNPs, 59.4 % were transitions and 40.6 % were transversions. A total of 213,758 SNPs, consisting of 122,327 non-synonymous and 91,431 synonymous SNPs, were identified in coding sequences. For SNP validation, 96 SNPs in the genic region were chosen from among IT213134 contigs longer than 10 kb. Of these 96 SNPs, 88 were confirmed by Sanger sequencing of 10 adzuki bean genotypes from various geographic origins as well as IT213134 and its wild relative IT178530. These genome-wide SNP markers will enrich the existing Vigna resources and, specifically, could be of value for constructing a genetic map and evaluating the genetic diversity of adzuki bean. [ABSTRACT FROM AUTHOR]

We have developed a kind of gold nanoparticle (AuNP) in which polyethylene glycol (PEG) and poly(N-isopropylacrylamide) (PNIPAM) are attached on the surface of a gold nanocrystal through the host–guest inclusion between adamantane groups (ADA) and β-cyclodextrin (β-CD). The resulting AuNPs become amphiphilic in water above body temperature and self-assemble into vesicles. It is found that these vesicles can load doxorubicin (Dox) effectively. With a decrease in temperature, the PNIPAM shifted from hydrophobic to hydrophilic, causing Au vesicles to disassemble into stable small AuNPs, triggering the release of Dox. These hybrid vesicles, combining polymer functionality with the intriguing properties of AuNPs, can first release free Dox and AuNP/Dox at a site of a tumor through the application of either simple ice packs or deeply penetrating cryoprobes, then the AuNP/Dox can be taken in by tumor cells and destroy them like miniature munitions. Furthermore, these vesicles showed other therapeutic possibilities due to the presence of gold. We believe that the development of such multi-functional vesicles will provide new and therapeutically useful means for medical applications. [ABSTRACT FROM AUTHOR]

The coexistence of three intracranial lesions related to epileptic pathogenesis is known as 'triple pathology' and has rarely been reported. In this study we report a case of temporal lobe epilepsy (TLE) with the coexistence of hippocampal sclerosis (HS), focal cortical dysplasia (FCD) and ganglioglioma in the temporal lobe. A 29-year-old male who had experienced recurrent seizures for four years was admitted to hospital. Cerebral magnetic resonance imaging (MRI) was conducted and T2-weighted and fluid-attenuated inversion recovery sequence (FLAIR) images revealed a reduced hippocampal volume with an increased FLAIR signal on the right side and a slightly enlarged temporal horn, which are typical imaging findings for HS and FCD. The patient underwent resectioning of the right anterior temporal lobe, hippocampus and amygdala, in addition to the lesion located in the medial temporal lobe. Immunohistochemical analysis of the medial temporal lobe lesion confirmed a ganglioglioma (WHO grade I) in the medial temporal lobe. During the first eight months following surgery, the patient's seizures were controlled with zonisamide and phenytoin. Electroencephalogram (EEG) assessment post-surgery confirmed the absence of epileptic discharges. Based on a literature review and a detailed review of this case, we postulate two possible explanations for the pathogenesis of 'triple pathology': i) 'triple pathology' is a combination of pathological progression and occasionality; and ii) 'triple pathology' lesions have similar pathological origins. [ABSTRACT FROM AUTHOR]

Blood viscosity has been considered as one of important biophysical parameters for effectively monitoring variations in physiological and pathological conditions of circulatory disorders. Standard previous methods make it difficult to evaluate variations of blood viscosity under cardiopulmonary bypass procedures or hemodialysis. In this study, we proposed a unique microfluidic device for simultaneously measuring viscosity and flow rate of whole blood circulating in a complex fluidic network including a rat, a reservoir, a pinch valve, and a peristaltic pump. To demonstrate the proposed method, a twin-shaped microfluidic device, which is composed of two half-circular chambers, two side channels with multiple indicating channels, and one bridge channel, was carefully designed. Based on the microfluidic device, three sequential flow controls were applied to identify viscosity and flow rate of blood, with label-free and sensorless detection. The half-circular chamber was employed to achieve mechanical membrane compliance for flow stabilization in the microfluidic device. To quantify the effect of flow stabilization on flow fluctuations, a formula of pulsation index (PI) was analytically derived using a discrete fluidic circuit model. Using the PI formula, the time constant contributed by the half-circular chamber is estimated to be 8 s. Furthermore, flow fluctuations resulting from the peristaltic pumps are completely removed, especially under periodic flow conditions within short periods (T < 10 s). For performance demonstrations, the proposed method was applied to evaluate blood viscosity with respect to varying flow rate conditions [(a) known blood flow rate via a syringe pump, (b) unknown blood flow rate via a peristaltic pump]. As a result, the flow rate and viscosity of blood can be simultaneously measured with satisfactory accuracy. In addition, the proposed method was successfully applied to identify the viscosity of rat blood, which circulates in a complex fluidic network. These observations confirm that the proposed method can be used for simultaneous measurement of viscosity and flow rate of whole blood circulating in the complex fluid network, with sensorless and label-free detection. Furthermore, the proposed method will be used in evaluating variations in the viscosity of human blood during cardiopulmonary bypass procedures or hemodialysis. [ABSTRACT FROM AUTHOR]

Accurate measurement of blood viscoelasticity including viscosity and elasticity is essential in estimating blood flows in arteries, arterials, and capillaries and in investigating sub-lethal damage of RBCs. Furthermore, the blood viscoelasticity could be clinically used as key indices in monitoring patients with cardiovascular diseases. In this study, we propose a new method to simultaneously measure the viscosity and elasticity of blood by simply controlling the steady and transient blood flows in a microfluidic analogue of Wheastone-bridge channel, without fully integrated sensors and labelling operations. The microfluidic device is designed to have two inlets and outlets, two side channels, and one bridge channel connecting the two side channels. Blood and PBS solution are simultaneously delivered into the microfluidic device as test fluid and reference fluid, respectively. Using a fluidic-circuit model for the microfluidic device, the analytical formula is derived by applying the linear viscoelasticity model for rheological representation of blood. First, in the steady blood flow, the relationship between the viscosity of blood and that of PBS solution (μBlood/μPBS) is obtained by monitoring the reverse flows in the bridge channel at a specific flow-rate rate (QPBSSS/QBloodL). Next, in the transient blood flow, a sudden increase in the blood flow-rate induces the transient behaviors of the blood flow in the bridge channel. Here, the elasticity (or characteristic time) of blood can be quantitatively measured by analyzing the dynamic movement of blood in the bridge channel. The regression formula (ABlood (t) = Aα + Aβ exp [-(t - t0)/λBlood]) is selected based on the pressure difference (ΔP = PA - PB) at each junction (A, B) of both side channels. The characteristic time of blood (λBlood) is measured by analyzing the area (ABlood) filled with blood in the bridge channel by selecting an appropriate detection window in the microscopic images captured by a high-speed camera (frame rate = 200 Hz, total measurement time = 7 s). The elasticity of blood (GBlood) is identified using the relationship between the characteristic time and the viscosity of blood. For practical demonstrations, the proposed method is successfully applied to evaluate the variations in viscosity and elasticity of various blood samples: (a) various hematocrits form 20% to 50%, (b) thermal-induced treatment (50 °C for 30 min), (c) flow-induced shear stress (53 ± 0.5 mL/h for 120 min), and (d) normal rat versus spontaneously hypertensive rat. Based on these experimental demonstrations, the proposed method can be effectively used to monitor variations in viscosity and elasticity of bloods, even with the absence of fully integrated sensors, tedious labeling and calibrations. [ABSTRACT FROM AUTHOR]

Mungbean [ Vigna radiata (L.) Wilczek], a self-pollinated diploid plant with 2 n = 22 chromosomes, is an important legume crop with a high-quality amino acid profile. Sequence variation at the whole-genome level was examined by comparing two mungbean cultivars, Sunhwanokdu and Gyeonggijaerae 5, using Illumina HiSeq sequencing data. More than 40 billion bp from both mungbean cultivars were sequenced to a depth of 72×. After de novo assembly of Sunhwanokdu contigs by ABySS 1.3.2 (N50 = 9,958 bp), those longer than 10 kb were aligned with Gyeonggijaerae 5 reads using the Burrows-Wheeler Aligner. SAMTools was used for retrieving single nucleotide polymorphisms (SNPs) between Sunhwanokdu and Gyeonggijaerae 5, defining the lowest and highest depths as 5 and 100, respectively, and the sequence quality as 100. Of the 305,504 single-base changes identified, 40,503 SNPs were considered heterozygous in Gyeonggijaerae 5. Among the remaining 265,001 SNPs, 65.9 % (174,579 cases) were transitions and 34.1 % (90,422 cases) were transversions. For SNP validation, a total of 42 SNPs were chosen among Sunhwanokdu contigs longer than 10 kb and sharing at least 80 % sequence identity with common bean expressed sequence tags as determined with est2genome. Using seven mungbean cultivars from various origins in addition to Sunhwanokdu and Gyeonggijaerae 5, most of the SNPs identified by bioinformatics tools were confirmed by Sanger sequencing. These genome-wide SNP markers could enrich the current molecular resources and might be of value for the construction of a mungbean genetic map and the investigation of genetic diversity. [ABSTRACT FROM AUTHOR]

Prostate-specific antigen (PSA) is a protein highly expressed in cancer cells of the prostate gland. In this study, the PSA recombinant protein was fused to the human immunoglobulin G crystallizable fragment (Fc) with the endoplasmic reticulum (ER) Lys-Asp-Glu-Leu (KDEL) retention signal tag for the plant expression system. Agrobacterium-mediated plant transformation was applied to generate transgenic tobacco plants expressing PSA tagged to KDEL (PSAK), PSA-Fc, and PSA-Fc fused to KDEL (PSA-FcK). Western blot analysis showed that the PSA-FcK protein was the most highly expressed among the three different proteins in the transgenic plant leaf. The PSAK, PSA-Fc, and PSA- FcK proteins were successfully purified from plant leaves. Reduced and non-reduced sodium dodecyl sulfate–polyacrylamide gel electrophoresis revealed that the PSA proteins fused to Fc and FcK were dimerized, whereas the PSA itself was not dimerized. N-glycan analysis demonstrated that the N-glycan profile of the PSA-Fc was mainly the structure with α(1,3)-fucose (Fuc) or β(1,2)-xylose (Xyl) glycan residues, whereas the PSA-Fc tagged with the KDEL ER retention signal had mainly an oligomannose-type structure. ELISA and SPR showed that PSA-FcK had a higher binding activity to Fc gamma receptor I than PSA-Fc and human Fc. In addition, PSA-FcK induced anti-PSA, and thus has the potential to be utilized as a prostate cancer vaccine. [ABSTRACT FROM AUTHOR]

To study the transmission characteristics of near-field detonation noise into water, the detonation noise transmission system is built on a laboratory-scale water tank using a detonation tube with a diameter of 30 mm. The interaction of the detonation gas jet with the air–water interface, the development of the cavity, and the growth of the liquid column are experimentally observed by a high-speed camera. The spectral distribution characteristics of detonation noise above and below the interface are recorded by a microphone, a hydrophone, and an underwater blast sensor. Analysis of the experimental images shows that the size of the cavity increases with increasing filling pressure and decreases with increasing nozzle height. By normalizing the evolution time of the cavity with the cavity lifetime, it is concluded that the time for the cavity to develop to the deepest is about 0.27, independent of the filling pressure. The pressure field data analysis results show that the main frequencies of the detonation sound waves are 100 and 400 Hz, and the frequency distribution has nothing to do with the filling pressure. Through the defined acoustic wave energy transmission coefficient, it is demonstrated that the detonation acoustic wave transmission coefficient decreases with the increase in the frequency, and the shock wave transmission coefficient decreases with the increase in the angle. [ABSTRACT FROM AUTHOR]

Objectives: To study the effectiveness of a dentifrice containing polyvinylmethyl ether-maleic acid (PVM/MA) copolymer in occluding dentin tubules and investigate the interaction between PVM/MA and type I collagen using surface plasmon resonance (SPR). Materials and methods: Fifteen volunteers brushed dentin discs in situ using dentifrices with and without PVM/MA copolymer in a cross-over design. Dentin tubule occlusion was evaluated after brushing, after overnight saliva challenge in vivo for 12 h and after drinking 250 ml of orange juice. Dentin tubule occlusion and tubule size were compared between the two groups using repeated ANOVA and before and after erosive challenges using paired t tests. SPR using type I collagen as ligand and PVM/MA as analyte was performed to evaluate the binding of the two macromolecules. Results: A median of 91 % of dentin tubules were occluded after a single brushing in the PVM/MA group, as compared to 9 % in the controls. After overnight saliva challenge and 10 min of erosion by orange juice, a median of 73 % of the dentin tubules remained fully occluded in the PVM/MA group as compared to zero in the controls. Dentin tubule size increased after orange juice erosion in the controls but not in the PVM/MA group. SPR study showed that PVM/MA bound readily to collagen molecules in a 4 to 1 ratio. Conclusions: Dentifrice containing PVM/MA could effectively occlude dentin tubules and prevent dentin erosion. PVM/MA may improve adhesive retention of intra-tubular dentifrice plugs through binding to dentin surface collagen. Clinical relevance: Brushing with dentifrice containing adhesive polymers has preventive effect against dentin erosion and dentin sensitivity. [ABSTRACT FROM AUTHOR]

Vx-770 (Ivacaftor), a Food and Drug Administration (FDA)-approved drug for clinical application to patients with cystic fibrosis (CF), shifts the paradigm from conventional symptomatic treatments to therapeutics directly tackling the root of the disease: functional defects of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel caused by pathogenic mutations. The underlying mechanism for the action of Vx-770 remains elusive partly because this compound not only increases the activity of wild-type (WT) channels whose gating is primarily controlled by ATP binding/hydrolysis, but also improves the function of G551D-CFTR, a disease-associated mutation that abolishes CFTR's responsiveness to ATP. Here we provide a unified theory to account for this dual effect of Vx-770. We found that Vx-770 enhances spontaneous, ATP-independent activity of WT-CFTR to a similar magnitude as its effects on G551D channels, a result essentially explaining Vx-770's effect on G551D-CFTR. Furthermore, Vx-770 increases the open time of WT-CFTR in an [ATP]-dependent manner. This distinct kinetic effect is accountable with a newly proposed CFTR gating model depicting an [ATP]-dependent "reentry" mechanism that allows CFTR shuffling among different open states by undergoing multiple rounds of ATP hydrolysis. We further examined the effect of Vx-770 on R352C-CFTR, a unique mutant that allows direct observation of hydrolysis-triggered gating events. Our data corroborate that Vx-770 increases the open time of WT-CFTR by stabilizing a posthydrolytic open state and thereby fosters decoupling between the gating cycle and ATP hydrolysis cycle. The current study also suggests that this unique mechanism of drug action can be further exploited to develop strategies that enhance the function of CFTR. [ABSTRACT FROM AUTHOR]

This review focuses on the most recent findings on the gating mechanism of CFTR. [ABSTRACT FROM AUTHOR]

Cystic fibrosis transmembrane conductance regulator (CFTR) is a unique member of the ATP-binding cassette (ABC) protein superfamily. Unlike most other ABC proteins that function as active transporters, CFTR is an ATP-gated chloride channel. The opening of CFTR's gate is associated with ATP-induced dimerization of its two nucleo-tide-binding domains (NBD1 and NBD2), whereas gate closure is facilitated by ATP hydrolysis-triggered partial separation of the NBDs. This generally held theme of CFTR gating--a strict coupling between the ATP hydrolysis cycle and the gating cycle--is put to the test by our recent finding of a short-lived, post-hydrolytic state that can bind ATP and reenter the ATP-induced original open state. We accidentally found a mutant CFTR channel that exhibits two distinct open conductance states, the smaller Ol state and the larger 02 state. In the presence of ATP, the transition between the two states follows a preferred Ol-->02 order, a telltale sign of a violation of microscopic reversibility, hence demanding an external energy input likely from ATP hydrolysis, as such preferred gating tran-sition was abolished in a hydrolysis-deficient mutant. Interestingly, we also observed a considerable amount of opening events that contain more than one Ol-->02 transition, indicating that more than one ATP molecule may be hydrolyzed within an opening burst. We thus conclude a nonintegral stoichiometry between the gating cycle and ATP consumption. Our results lead to a six-state gating model conforming to the classical allosteric mecha-nism: both NBDs and transmembrane domains hold a certain degree of autonomy, whereas the conformational change in one domain will facilitate the conformational change in the other domain. [ABSTRACT FROM AUTHOR]

Asymmetric‐type UV photodetectors have attracted extensive interest for their applications in modern optoelectronics. Conventional fabrication approaches for asymmetric metal contacts typically cause damage at the metal‐semiconductor interface, leading to Fermi level pinning and further limiting barrier height adjustability and functionality. Herein, for the first time, van der Waals (vdW) asymmetric metal contact on wide bandgap semiconductor gallium‐nitride (GaN) is successfully fabricated and achieve the mitigation of Fermi level pinning effect through the formation of a damage‐free metal‐semiconductor interface. Scanning transmission electron microscopy reveals an atomically clean and sharp interface with a distinct vdW gap between the semiconductor and metal electrode. More importantly, the absence of interface damage effectively suppresses charge recombination and results in substantial enhancement in photoresponse characteristics, demonstrating an increased responsivity from 1.8 to 56.7 A W−1 along with a significantly improved response/recovery time from 545/115 to 420/20 ms and an ultralow dark current at the picoampere‐level compared to that of the photodetector with electrodes fabricated with traditional e‐beam evaporated technique. Such simultaneously enhanced responsivity and response speed overcome the responsivity‐speed trade‐off in asymmetric photodetectors and mark a milestone in integrating asymmetric metal contacts with semiconductors through a non‐destructive manner, offering unparalleled opportunities for developing high‐performance asymmetric optoelectronic systems. [ABSTRACT FROM AUTHOR]

Highlights: A novel photoelectrochemical (PEC) photosensor composed of GaN nanowire-on-Si platform demonstrates record-high responsivity of 247.8 mA W−1 with ultra-stable operation characteristics. Strategic internal and external band structure engineering of semiconductor nanowires promotes efficient PEC reaction via controlling carrier dynamics while preserving nanowires from material degradation. The glucose sensing system is constructed to successfully analyze blood glucose levels in real human serum samples, featuring a high sensitivity of 0.173 µA µM−1 cm−2 and a low detection limit of 0.07 µM. Photosensors with versatile functionalities have emerged as a cornerstone for breakthroughs in the future optoelectronic systems across a wide range of applications. In particular, emerging photoelectrochemical (PEC)-type devices have recently attracted extensive interest in liquid-based biosensing applications due to their natural electrolyte-assisted operating characteristics. Herein, a PEC-type photosensor was carefully designed and constructed by employing gallium nitride (GaN) p–n homojunction semiconductor nanowires on silicon, with the p-GaN segment strategically doped and then decorated with cobalt–nickel oxide (CoNiOx). Essentially, the p–n homojunction configuration with facile p-doping engineering improves carrier separation efficiency and facilitates carrier transfer to the nanowire surface, while CoNiOx decoration further boosts PEC reaction activity and carrier dynamics at the nanowire/electrolyte interface. Consequently, the constructed photosensor achieves a high responsivity of 247.8 mA W−1 while simultaneously exhibiting excellent operating stability. Strikingly, based on the remarkable stability and high responsivity of the device, a glucose sensing system was established with a demonstration of glucose level determination in real human serum. This work offers a feasible and universal approach in the pursuit of high-performance bio-related sensing applications via a rational design of PEC devices in the form of nanostructured architecture with strategic doping engineering. [ABSTRACT FROM AUTHOR]

Drug-based supramolecular self-assembling delivery systems have enhanced the bioavailability of chemotherapeutic drugs and reduced systemic side effects; however, improving the delivery efficiency and responsive release ability of these systems remains challenging. This study focuses primarily on the utilization of per-6-thio-β-cyclodextrin (CD) to link a significant quantity of paclitaxel (PTX) via ROS-sensitive thioketal (TK) linkages (designated as CDTP), thereby allowing efficiently drug release when exposed to high levels of reactive oxygen species (ROS) in the tumor microenvironment. To construct these supramolecular nanoparticles (NPs) with CDTP, we introduced PEGylated ferrocene (Fc) through host-guest interactions. The intracellular hydrogen peroxide (H 2 O 2) is converted into hydroxyl radicals (•OH) through the Fc-catalyzed Fenton reaction. Additionally, the generated Fc+ consumes the antioxidant glutathione (GSH). In both in vivo and in vitro experiments, CDTP@Fc-PEG NPs were absorbed effectively by tumor cells, which increased levels of ROS and decreased levels of GSH, disrupting the redox balance of cancer cells and increasing their sensitivity to chemotherapy. Furthermore, CDTP@Fc-PEG NPs exhibited high tumor accumulation and cytotoxicity without causing significant toxicity to healthy organs. Collectively, our results suggest CDTP@Fc-PEG NPs as a promising supramolecular nano-delivery platform for high drug-loading of PTX and synergistic chemotherapy. [Display omitted] • The ROS-driven supramolecular NPs has been constructed successfully and corresponding characterizations have been conducted. • Supramolecular prodrug nano-delivery system that can respond to the TME, while also demonstrating a high drug-loading capacity and delivery efficiency. • The results show that the nanoparticle can deplete GSH and amplify ROS simultaneously, resulting in the disruption of redox homeostasis. And the chemosensitization due to redox imbalance has also verified. • The results of in vitro and in vivo experiments both confirmed the excellent antitumor capability and favorable biosafety of the nanoparticle. [ABSTRACT FROM AUTHOR]

The properties of noncovalent complexes of the enzyme exo-1,4-β-D-glycanase ('Cex') with three aza-sugar inhibitors, deoxynojirimycin (XDNJ), isofagomine lactam (XIL), and isofagomine (XIF), have been studied with solution and gas-phase hydrogen deuterium exchange (H/Dx) and measurements of collision cross sections of gas-phase ions. In solution, complexes have lower H/Dx levels than free Cex because binding the inhibitors blocks some sites from H/Dx and reduces fluctuations of the protein. In mass spectra of complexes, abundant Cex ions are seen, which mostly are formed by dissociation of complexes in the ion sampling interface. Both complex ions and Cex ions formed from a solution containing complexes have lower cross sections than Cex ions from a solution of Cex alone. This suggests the Cex ions formed by dissociation 'remember' their solution conformations. For a given charge, ions of the complexes have greater gas-phase H/Dx levels than ions of Cex. Unlike cross sections, H/Dx levels of the complexes do not correlate with the relative gas-phase binding strengths measured by MS/MS. Cex ions from solutions with or without inhibitors, which have different cross sections, show the same H/Dx level after 15 s, indicating the ions may fold or unfold on the seconds time scale of the H/Dx experiment. Thus, cross sections show that complexes have more compact conformations than free protein ions on the time scale of ca. 1 ms. The gas-phase H/Dx measurements show that at least some complexes retain different conformations from the Cex ions on a time scale of seconds. [ABSTRACT FROM AUTHOR]

Hemoglobin (Hb) (αβ) is a tetrameric protein-protein complex. Collision cross sections, hydrogen exchange levels, and tandem mass spectrometry have been used to investigate the properties of gas-phase monomer, dimer, and tetramer ions of adult human hemoglobin (Hb A, αβ), and two variant hemoglobins: fetal hemoglobin (Hb F, αγ) and sickle hemoglobin (Hb S, αβ, E6V[β]). All three proteins give similar mass spectra. Monomers of Hb S and Hb F have similar cross sections, ca. 10% greater than those of Hb A. Cross sections of dimer ions of Hb S are 11% greater than those of Hb A and 6% greater than those of Hb F. Tetramers of Hb S are 13% larger than tetramers of Hb A or Hb F. Monomers and dimers of all three Hb have similar hydrogen-deuterium exchange (HDX) levels. Tetramers of Hb S exchange 16% more hydrogens than Hb A and Hb F. In tandem mass spectrometry, monomers of Hb S and Hb F require ca. 10% greater internal energy for heme loss than Hb A. Dimers (+11) of Hb A and Hb S dissociate to monomers with asymmetrical charge division; dimers of Hb F (+11) dissociate with nearly equal charge division. Tetramer ions dissociate to monomers and trimers, unlike solution Hb, which dissociates to dimers. The most stable dimers are from Hb S; the most stable tetramers from Hb F. The results with Hb S show that a single mutation in the β chain can change the physical properties of this gas-phase protein-protein complex. [ABSTRACT FROM AUTHOR]

In computer tomography (CT), truncated projections are produced due to scanning large objects with a detector that is limited in width. Applying filtered back-projection(FBP) method directly to truncated projections, the reconstructed image will contain truncation artifacts - bright rings on the boundary of region of interest (ROI). Extrapolation algorithms can be used to reduce the truncation artifacts; however extrapolations are usually double the length of the projection data; resulting in an increased calculation time. This paper introduces mixed extrapolation, which is a combination of exponential and quadratic extrapolation. It is proven that doubling the length of the projection data for the mixed extrapolation can be avoided. The projections were extrapolated according to the boundary values and their derivatives. The algorithm achieves equivalence to the extrapolation approach with negligible increased calculation time. Supplementary functions are introduced in order to simplify the calculations. These functions can be calculated prior to extrapolation process, hence the calculation time is significantly reduced. The calculation times are compared between fast extrapolation introduced in this paper and normal extrapolation with doubling the length of projection data. [ABSTRACT FROM AUTHOR]